In general, a computer is connected to various peripherals. Among the computer peripherals, there is a device equipped with a self-power cutoff function for saving power, when the computer is placed in power saving mode. For example, a monitor turns off its screen in the power saving mode, thus reducing power consumption to about 15 W. When the computer is turned off, the monitor deactivates its function and enters standby state, consuming usually a standby power of about 4 W. A printer also consumes about 4 W all the time.
As described above, when a computer is in the power saving mode, computer peripherals conventionally consume minimum power to reduce unnecessary power consumption. When the computer is turned off, they consume minimum standby power. Thus, the standby power is always consumed.